As fossil fuel has been exhausted, many power generation apparatus using natural power have been developed. As one example of the power generation apparatus, there is a power generation apparatus using solar heat. The power generation apparatus using solar heat includes a solar heat power generation system. As one example of solar heat power generation system, there is a tower-type solar heat power generation system.
The tower-type solar heat power generation system includes several heliostats for tracking the sun, and reflecting and collecting sunlight to be focused onto a place, a receiver for absorbing the energy of the collected solar heat to transfer the energy to a heat transfer medium, a steam generator for generating steam by using the heat of the heat transfer medium heated in the receiver, and a steam turbine for generating electricity by using the steam generated from the steam generator.
In the tower-type solar heat power generation system, the heat transfer medium passing through the receiver is heated by the heat collected by the heliostats. The heat transfer medium heated up to about 1,000 degrees in the receiver is transferred to the steam generator, so that the steam generator generates saturated or over-heated steam. In this case, the generated steam is transferred to the steam turbine to generate power.
In the tower-type solar heat power generation system, if air serves as the heat transfer medium, the air used in the steam generator may return again to the receiver through a fan. For the purpose of preparing for the reduction of radiation energy of the sun as an energy source, the heat energy may be stored in a heat storage tank. That is, the tower-type solar heat power generation system includes a heliostat, a tower, a storage, a turbine, a generator, a condenser, and a deaerator
As shown in FIG. 5, the tower and air-type receiver according to the prior art includes a plurality of receiver modules 2 installed at a front end of the receiver 1 to suck external air through an inner suction fan. The receiver module 2 is heated at a high temperature when the sunlight reflected upon the heliostat is collected. In this case, when the inner suction fan is driven, external air is introduced along a fine passage of the receiver module 2 therein. Then, the introduced external air makes a heat exchange with the receiver module while passing through the receiver module, so that the temperature of the introduced external air is raised to a high temperature, Thus, steam is generated by using the external air heated at the high temperature, so that electric power may be generated.
However, since the absorber according to the prior art has a rear portion which is exposed to an outside or directly connected to a support and is insufficient to transfer solar heat, so that the rear portion has relatively lower temperature than a front portion thereof. Thus, there is a problem that causes the high-temperature air passing through the receiver module to make a heat re-exchange through a wall surface of the rear portion of the absorber, thereby losing heat.
Therefore, there is a need to study an absorber having a structure capable of minimizing the heat loss due to the heat re-exchange at the rear portion of the absorber.